Rotary dressing apparatus

ABSTRACT

A rotary dressing apparatus of increased rigidity for a multiwheel grinding machine is provided. A plurality of diamond rolls are carried at the forward end of slides each fitted in a dresser body. A table is disposed on a grinding wheel carriage rotatably supporting a plurality of grinding wheels and is connected with a feed unit for sliding movement in a direction perpendicular to the axis of the grinding wheels. The table is formed with at least two T-shaped grooves extending parallel to the axis of the grinding wheels, and pivot support blocks are mounted in one of the grooves and support pivot pins with their axes perpendicular to both the direction of the sliding movement of the table and the axis of the grinding wheels. Dresser bodies are placed on the table for angular movement about the respective pivot pins, and are normally fixed to the table by T-nuts received in the other groove and bolts threadably engaging therewith.

United States Patent 1191 Ota Mar. 5 1974 ROTARY DRESSING APPARATUS Primary Examinerl-laro1d D. Whitehead [75] Inventor: Hiroshi 0m, Kariya, Japan Attorney, Agent, or FirmWende'roth, Lind & Ponack [73] Assignee: Toyoda Koki Kabushiki Kaisha,

Aichi-ken, Japan [571 ABSTRACT [22] Filed: May 22, 1972 A rotary dressingapparatus of increased rigidity for a multl-wheel grmdmg machine 15 provlded. A plurahty PP 255,273 of diamond rolls are carried at the forward end of Hill 125/11 R X slides each fitted in a dresser body; A table is disposed on a grinding wheel carriage rotatably supporting a plurality of grinding wheels and is connected with a feed unit for sliding movement in a direction perpendicular to the axis of the grinding wheels. The table is fomied with at least two T-shaped grooves extending parallel to the axis of the grinding wheels, and pivot support blocks are mounted in one of the groovesand support pivot pins with their axes perpendicular to both the direction of the sliding movement of the table and the axis of the grinding wheels. Dresser bodies are placed on the table for angular movement about the respective pivot pins, and are normally fixed to the table by T-nuts received in the other groove and bolts threadably engaging therewith.

6 Claims, 2 Drawing Figures ROTARY DRESSING APPARATUS BACKGROUND OF THE INVENTION The invention relates to a rotary dressing apparatus having an array of a plurality of diamond'rolls and provides a rotary dressing apparatus of increased rigidity.

A rotary dressing apparatus for a multi-whee] grinding machine must have an independent provision of a feeding device and a taper adjustingdevice for each of the diamond rolls corresponding to separate grinding wheels in order to maintain the desired accuracy in the size of the work. In the prior art, this has been met by an arrangement in which a plurality of dresser bodies are fixedly mounted on a table which serves for feeding a plurality of diamond rolls simultaneously and each dresser body is provided with a slidable slide. A dresser head carrying a diamond roll is pivotably mounted on the front end of the slidable slide. I v However, the pressure exerted on a diamond roll when dressing is of such a magnitude that the rotary dressing apparatus of the-prior art arrangement employing a pivotal mounting of a dresser head on the slide results in a insufficient rigidity to produce a dressed surface of high accuracy due to vibrations.

SUMMARY OF THE INVENTION The invention overcomes the above disadvantages, and resides in the arrangement of a plurality of dresser bodies each pivotally mounted on a table which serves for simultaneously feeding forward a plurality of diamond rolls in a manner such that each dresser body is adjustably positionedin a direction parallel to' the axis of the grinding wheel spindle and the provision of a slide carrying a diamond roll which is slidably fitted in the dresser body.

BRIEF DESCRIPTION OF DRAWINGS The above and other objects, features and advantages of the invention will become apparent as the description proceeds with reference to the drawings illustrating one embodiment of the invention and in which FIG. I is a longitudinal section of the rotary dressing apparatus, and

FIG. 2 is a plan view, partly in section, of the apparatus.

DETAILED DESCRIPTION OF INVENTION Referring to the drawings, numeral 1 denotes a grinding wheel carriage on which grinding wheels 2a, 2b and 2c are mounted. On the grinding wheel carriage l is placed a table 3 having a feed nut 4 secured to the bottom surface thereof. Feed nut 4 is threadably engaged by a threaded fccd shaft 5 of a table feed unit (not shown) mounted on the rear part of the carriage l. The

table 3 is arranged to be slidable in a direction perpen-- dicular to the axis of a grinding wheel spindle and is adapted to move toward or away from the grinding wheels 2a, 2b and 20 upon operation of the table feed unit to initiate rotation of the feed shaft '5.

Pivotally mounted on the table 3 and opposite to the respective grinding wheels 2a, 2b and 2c are dresser bodies a, 10b and 100. These are normally fixed to the table 3 by means of bolts 11, packing rings 12 mounted thereon and T-shaped grooves 13 formed in the top surface of the table 3 running parallel to the axis of the grinding wheels. T-nuts 14 are received in the T-shaped 15a, 15b and 150, respectively and are threadably engaged by the threaded feed shafts of slide feed units 17a, 17b and 17c mounted on the rear part of the dresser bodies 10a, 10b and 10c, respectively, for advancing and retracting an individual one of the slides 15a, 15b and 150. Only one of these shafts (18b) is shown. However, it should be understood that similar shafts are employed with slide feed units 17a and 17c. Furthermore, it should be noted that for the sake of simplicity, when only one reference numeral having a lettered postscript is used to described a particular element in the remainder of the specification, it should be understood that each of the dresser bodies l0a-l0c contains a similar element.

To the forward end of the slides 15a, 15b and 15c which oppose the grinding wheels 2a, 2b and 2c are se-' cured roll bearing blocks 20a, 20b and 20c,

respectively, on the top surface of which are secured driving shaft bearings blocks such as 21a and 21b. The roll bearing blocks 20a, 20b and 200 rotatably carry dresser shafts, one of which is shown at 220, with their axes running parallel to the axis of the grinding wheels. Diamond rolls 23a 23b and 23C are secured to'the dresser shafts 22a, 22b and 22c at a central portion thereof and gears 24a are secured to one end of these dresser shafts. Driving shafts 25a, 25b and 250, have their axes running parallel to the axis of the grinding wheels, and adjacent pairs of these shafts are connected together by means of couplings shown at 260 which comprise torque springs. Gears 27a and 27b and a similar third gear are locked onthe respective driving shafts 25a, 25b and 250 and mesh with'the three gears respectively, secured to the dresser shafts 22a, 22b. On the external side surface of one of the driving shaft bearing blocks, 21a, secured by way of a support block 30 is a bearing block 31, in which is rotatably carried a rotary shaft 32 in alignment with the axis of the driving shaft 25a. The rotary shaft 32 is connected with the driving shaft 25a and is connected through a transmission system comprising a timing pulley and a belt with a drive motor 33 thatis fixedly mounted on the table 3 for the purpose of driving the diamond rolls. Thus the arrangement is such that upon operating of the motor 33, the diamond rolls 23a, 23b and 230 are rotated through the series of interposed mechanisms. In order that desired dimensional accuracy of the work can be achieved, the slidefeed units 17a 17b and are separately operated to control the amount of feed imparted to the diamond rolls 23a, 23b and 230 independently, and if the driving shafts 25a, 25b and 250 have their axis offset from or excentric to each other, the rotation of the diamond rolls 23a, 23b and 23c will not be effected because of the couplings which provide a flexibleinterconnection between them.

The rotary dressing apparatus is also provided with a taper control. In the side wall opposite each of the grinding wheels 2a, 2b and 2c, the table 3 is formed with a T-shaped groove 40 which extends parallel to the axis of the grinding wheels and receives T-nut 42b which is threadably engaged by bolt 43b for fixedly carrying pivot support block 41b. Pivot pin 44b is secured in the pivot bearing block 41b with its axis extending vertically and is located approximately immediately below the associated dresser shaft 22b and projects above the top surface of this block into pivotal and fitting engagement with pivot bearing 45b. This pivot bearing is secured to the dresser body 10b. Similar arrangements are secured to dresser bodies 10a and 10c, whereby the dresser bodies are pivotally movable on the table 3. A taper adjusting block 51 having a reference projection 50 extendingin the direction of movement of the slide 15b is secured to the rear part of dresser body 10b and is formed with a female thread which extends therethrough in a direction parallel to the axis of the grinding wheels. Gauge stands 54 and 55 carrying dial gauges 52 and 53, respectively, are secured to the rear part of the dresser bodies 10a and 106 and rotatably carry taper adjusting bolts 56 and 57 which are restrained from axial movement. The bolts 56 and 57 are threaded at their forward end where they threadably engage with the taper adjusting block 51 from the opposite sides thereof.

Taper adjustment which may be found necessary upon examining work subjected to a grinding operation to improve dissatisfactory tapering at given locations can be understood from the following description given in connection with the diamond roll 23c.

Fixing bolts 11 clamping the dresser body 100 are loosened to allow its angular movement on the table 3 and the contact piece associated with the dial gauge 53 is brought into contact with the reference projection 50 of the taper adjusting block 51. The turning of the taper adjusting bolt 57 through a desired angle based on the indication on the dial gauge 53 produces an angular movement of the dresser body 100 about its associated pivot pin. This is due to the fact that the dresser body lb is fixed to the table 3, where by the slide 150 fitted in the dresser body 100, roll bearing block 20c secured to this slide 150, dresser shaft 22c journalled in the bearing block 20c, and diamond roll 23c securely mounted on the dresser shaft 22c undergo integral angular movement with respect to the outer peripheral surface of the grinding wheel 2c. Upon adjustment, the dresser body c is fixed to the table 3 and the table 3 may be advanced for the dressing operation to remove the dissatisfactory taper.

From the foregoing, it will be understood that the rotary dressing apparatus of the invention incorporates an arrangement such that dresser bodies for holding slides fitted therein and carrying a plurality of diamond rolls are arranged on a table that serves to feed the diamond rolls forward simulataneously so as to be angularly movable and adjustable in the axial direction of the grinding wheels, with the consequence that the construction is simplified but has an increased rigidity such that the grinding surfaces of the grinding wheels can be dressed with high precision even with an increased force applied in the rotary dressing process. 7

Having described the invention, what is claimed is l. A rotary dressing apparatus comprising a table disposed on a grinding wheel carriage which rotatably supports a plurality of grinding wheels, said table being operatively connected with a feed unit and being slidable in a direction perpendicular to the axis of the grinding wheels, said table including at least a pair of T-shaped grooves running parallel to the axis of the grinding whhels, a plurality of pivot support blocks mounted in one of the T-shaped grooves and adapted to be adjustably positioned, a plurality of pivot pins,

one each supported by each of the pivot support blocks with their axes perpendicular to both the direction of sliding movement of the table and the axis of the grinding wheels, a plurality of dresser bodies placed on the table for angular movement about each of the pivot pins and being normally fixed to the table by means of a T-nut received in the other T-shaped groove and a bolt threadably engaging therewith and a plurality of rotary dressing heads, at least one mounted on each of the dresser bodies.

2. A rotary dressing apparatus according to claim 1, further comprising a plurality of slides each slidably carried by one of said dresser bodies, said rotary dressing heads being secured to the forward end of said slides, each of the slides having a feed nut secured to the rear end thereof which is threadably engaged by a threaded feed shaft of a slide feed unit that is mounted on the rear part of each of said dresser bodies, thereby enabling the rotary dressing heads to be individually advanced or retracted.

3. A rotary dressing apparatus according to claim'2, in which each of the slides has secured to its forward end a roll bearing block on top of which is secured a driving shaft bearing block, said rolling bearing block rotatably carrying a dresser shaft and said driving shaft bearing block rotatably carrying a driving shaft, both the dresser shaft and driving shaft extending parallel to the axis of the grinding wheels, the driving shafts carried by separate driving shaft bearing blocks being connected together by means of a coupling which comprises a torque spring.

4. A rotary dressing apparatus according to claim 3, in which said pivot pins are located adjacent immedi ately below the respective dresser shafts and are pivotally connected with the respective dresser bodies.

5. A rotary dressing apparatus according to claim 3, in which each of the dresser shafts has a diamond roll secured to its medial portionand a gear secured to one of its ends, each of the driving shafts having a gear which meshes with the gear on the dresser shaft, one of the driving shafts being operatively connected with a motor means fixedly mounted on the table.

6. A rotary dressing apparatus according to claim 1, further including at least three dresser bodies and a plurality of slides each slidably carried by one of said dresser bodies, an intermediate one of said dresser bo-' dies having a taper adjusting block secured to its rear part, said taper adjusting block having an integral reference projection extending in the direction of sliding movement of the slide associated with the dresser body on which it is secured, said taper adjusting block being formed with a female thread having an axis extending parallel to the axis of the grinding wheels, the dresser bodies located on the opposite sides of said intermediate dresser body each having a gauge stand carrying a dial gauge, each of the gauge stands rotatably carrying a taper adjusting bolt which is restrained from its axial movement and which has a threaded end to threadably engage the thread in the taper adjusting block, each of said dial gauges having a contact piece that is adapted to be brought into contact with the reference projection to give an indication on the dial gauge in accordance with which the taper adjusting bolt is manually turned, thereby causing a pivotal movement of the as-,

sociated dresser body about the pivot pin with which it is associated. 

1. A rotary dressing apparatus comprising a table disposed on a grinding wheel carriage which rotatably supports a plurality of grinding wheels, said table being operatively connected with a feed unit and being slidable in a direction perpendiculaR to the axis of the grinding wheels, said table including at least a pair of T-shaped grooves running parallel to the axis of the grinding whhels, a plurality of pivot support blocks mounted in one of the T-shaped grooves and adapted to be adjustably positioned, a plurality of pivot pins, one each supported by each of the pivot support blocks with their axes perpendicular to both the direction of sliding movement of the table and the axis of the grinding wheels, a plurality of dresser bodies placed on the table for angular movement about each of the pivot pins and being normally fixed to the table by means of a T-nut received in the other T-shaped groove and a bolt threadably engaging therewith and a plurality of rotary dressing heads, at least one mounted on each of the dresser bodies.
 2. A rotary dressing apparatus according to claim 1, further comprising a plurality of slides each slidably carried by one of said dresser bodies, said rotary dressing heads being secured to the forward end of said slides, each of the slides having a feed nut secured to the rear end thereof which is threadably engaged by a threaded feed shaft of a slide feed unit that is mounted on the rear part of each of said dresser bodies, thereby enabling the rotary dressing heads to be individually advanced or retracted.
 3. A rotary dressing apparatus according to claim 2, in which each of the slides has secured to its forward end a roll bearing block on top of which is secured a driving shaft bearing block, said rolling bearing block rotatably carrying a dresser shaft and said driving shaft bearing block rotatably carrying a driving shaft, both the dresser shaft and driving shaft extending parallel to the axis of the grinding wheels, the driving shafts carried by separate driving shaft bearing blocks being connected together by means of a coupling which comprises a torque spring.
 4. A rotary dressing apparatus according to claim 3, in which said pivot pins are located adjacent immediately below the respective dresser shafts and are pivotally connected with the respective dresser bodies.
 5. A rotary dressing apparatus according to claim 3, in which each of the dresser shafts has a diamond roll secured to its medial portion and a gear secured to one of its ends, each of the driving shafts having a gear which meshes with the gear on the dresser shaft, one of the driving shafts being operatively connected with a motor means fixedly mounted on the table.
 6. A rotary dressing apparatus according to claim 1, further including at least three dresser bodies and a plurality of slides each slidably carried by one of said dresser bodies, an intermediate one of said dresser bodies having a taper adjusting block secured to its rear part, said taper adjusting block having an integral reference projection extending in the direction of sliding movement of the slide associated with the dresser body on which it is secured, said taper adjusting block being formed with a female thread having an axis extending parallel to the axis of the grinding wheels, the dresser bodies located on the opposite sides of said intermediate dresser body each having a gauge stand carrying a dial gauge, each of the gauge stands rotatably carrying a taper adjusting bolt which is restrained from its axial movement and which has a threaded end to threadably engage the thread in the taper adjusting block, each of said dial gauges having a contact piece that is adapted to be brought into contact with the reference projection to give an indication on the dial gauge in accordance with which the taper adjusting bolt is manually turned, thereby causing a pivotal movement of the associated dresser body about the pivot pin with which it is associated. 